Elongated hole brush

ABSTRACT

A ROTARY TUBULAR BRUSH HAVING A TUBULAR CORE, SAID CORE HAVING AXIALLY ELONGATED TUFT HOLES, AND TUFTS SECURED IN THE HOLES BY STAPLES. THE TUFT HOLES MAY BE FORMED BY, FOR EXAMPLE, A MACHINE THAT MOVES A ROTARY DRILL FOR DRILLING CIRCULAR HOLES FIRST DOWNWARDLY AND THEN UPWARDLY WHILE THE CORE IS MOVED AXIALLY. ALSO THE TUFT HOLES MAY BE FORMED BY BURNING, CASTING OR PUNCHING. ADDITIONALLY, BRUSHED OTHER THAN TUBULAR BRUSHED MAY HAVE TUFT HOLES FOR TUFTS THAT ARE OF A GREATER CROSS-SECTIONAL DIMENSION IN ONE DIRECTION THAN THE OTHER IN A PLANE PERPENDICULAR TO THE DEPTH DIRECTION OF THE HOLES.

[111 3,820,186 51 June 28, 1974 I ELONGATED HOLE BRUSH [75] Inventor:RalphC. Peabody, Minneapolis,

Minn.

[73] Assignee: Tennant Company, Minneapolis,

Minn.

[22] Filed: Mar. 29, 1972 [21] Appl. No.: 239,257

52] us. C1 15/182, 15/195, 300/8 51 Int. Cl. A461) 3/16,A46d H08 [58]Field of Search 15/191, 192, 193, 194,

FOREIGN PATENTS OR APPLICATIONS 177,208 10/1906 Germany 15/179 186,81612/1963 Sweden ..15/177 Primary ExaminerPeter Feldman Attorney, Agent,or Firm-Dugger, Johnson & Westman [5 7 ABSTRACT A rotary tubular brushhaving a tubular core, said core having axially elongated tuft holes,and tufts secured in the holes by staples. The tuft holes may be formedby, for example, a machine that moves a rotary drill for drillingcircular holes first downwardly and then upwardly while the core ismoved axially. Also the tuft holes may be formed by burning, casting orpunching. Additionally, brushes other than tubular brushes may have tuftholes for tufts that are of -a greater crosssectional dimension in onedirection than the other in a plane perpendicular to the depth directionof the holes.

7 Claims, 8 Drawing Figures PATENTEDMN 28 R124 SNEEI 1 F 2 1 ELONGATEDHOLE BRUSH BACKGROUND OF THE INVENTION A tubular brush having tuftssecured in holes in the tube.

' In prior art tubular brushes, for example, such as disclosed in U.S.Pat. No. 2,879,534 and U.S. Pat. No. 3,614,801, the tufts are mounted incircular holes having conical bottoms that extend radially relative thecentral axis of the brush. In U.S. Pat. No. 648,527 there is disclosed arotary brush wherein the tuft holes are circular and inclined relativeto the radius of the brush. In such prior art brushes a relatively largenumber of holes are required for mounting a given amount of tuftbristles. In order to reduce the number of tuft holes for mounting agiven amount of bristles, to obtain other economies in manufacture andto provide other advantages, this invention has been made.

SUMMARY OF THE INVENTION A tubular brush having tuft holes that areaxially elongated. I

One of the objects of this invention is to provide a brush having tuftholes of a new and novel shape. Another object of this invention is toprovide a new and novel brush that requires a substantially smallernumber of tuft holes to mount a given amount of tuft bris-.

tles than prior art brushes.

An additional object of this invention is to provide a brush having tuftholes that are elongated in a direction axially relative the brush core.In furtherance of the last mentioned object, it is another object toprovide opposed side wall portions, which in part define the tuft holes,that generally converge in a radially inward direction.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view,partly sectioned along a longitudinal axis, of a representative tubularbrush of this invention;

FIG. 2 is an end view of the brush of FIG. 1;

FIG. 3 is a fragmentary representation of the brush tube as though thetube were cut longitudinally and flattened; this view illustrating theouter surface of the brush tube after drilling and before tufting toshow an exemplary pattern of location of tuft holes;

FIG. 4 is an enlarged view of a portion of FIG. 3 to more clearly showthe tuft holes; 7

FIG. 5 is a fragmentary longitudinal cross-sectional view generallytakenalong the line and in the direction of the arrows 5-5 of FIG. 4;

FIG. 6 is a fragmentary transverse cross-sectional view generally takenalong the line and in the direction of the arrows 6-6 of FIG. 5 otherthan it additionally designated 10, includes a tube 11 having aplurality of holes 12 in which tufts 13 are secured by staples 14. Thetube may be made of a rigid foam thermoplastic material such asdisclosed in the above mentioned U.S.

Pat. No. 3,614,80l or of impregnated paper such as disclosed in U.S.Pat. No. 2,879,534 or other suitable materials.

Provided in the tube throughout the length L are a plurality of tuftholes 12, thepattern of the holes and the hole depths (l-ID)advantageously being similar to that disclosed in U.S. Pat. No.2,879,534. However, the shape of the holes is difierent. That is, eachof the holes 12 extends generally radially from the outer surface of thebrush and at the outer surface has an axial length X that issubstantially greater than the transverse width D. Further, the holesare shaped such that lines 15, 16 at the intersection of a plane of boththe central axis of the tube and the central axis CC of the hole withside wall surface portions defining a hole 12 from the generally conicalbottom 12a of the hole outwardly diverge at an included angle D (seeFIG. 5), while the lines 17, 18 of intersection of a plane of thecentral axis CC of the hole that is perpendicular to the central axis Cof the tube with the side wall surface portions defining the hole areparallel to one another and to the central axis of the hole (see FIG.6). It is preferred that the dimension X is about 40 percent greater ormore than the dimension D. The side wall surface portions defining eachhole from the conical bottom outwardly are smoothly, continuouslycurved.

A tube thickness TT of about l/2 inch to 5/8 inch is satisfactory inmost instances for a brush for scrubbing and sweeping purposes; althoughfor larger diameter brushes and heavy duty brushes, the thickness may beincreased to 1.0 inch or more. The hole depth is always less than thetube thickness to leave an underhole thickness UI-IT of asubstantial'dimension. Preferrably the hole depth is greater than thetransverse dimension D of the hole and about two-thirds of the tubethickness T1".

The tufts 13 are made of bristle suitable for the work to be done.Examples of suitable bristle material are set forth in U.S. Pat.2,879,534. Further, the staples 14 for retaining (anchoring) the tuftsin the holes and the manner of setting the staples is set forth in thelast mentioned patent.

Other than for the surface portions defining each hole 12 that areclosely adjacent the lines 17, 18 of intersection of the wall surfacesdefining the hole with a plane of the center axis of the hole CC that isperpendicular to the center axis C of the tube, the lines ofintersection of planes of the hole center axis C with the wall portionsdefining the hole outwardly of the conical bottom diverge. As a resultthe bristles are not as sharply bent and more bristles can be placed ineach hole than in brushes having circular tuft holes. Additionally dueto the bristles fanning outwardly from a location substantially inwardlyof the outer surface of the tube, the normal axial spread (dimension Y)of the bristles at their outer ends is greater than that where circularholes of the same cross-sectional area are provided. Additionally it ispreferred that the adjacent holes in each axial row of holes aresufficiently close that the bristles of tufts 13a, 13b in adjacent holes(see FIG. 7) overlap at their outer ends so that at least some of thebristles of one tuft have their outer ends located radially outwardly ofthe center part of the hole for the other tuft. This overlap closes anyopen space which would develop between tufts upon brush wear.

By using the axially elongated holes, there is obtained a flaredfanned-out tuft. Further, the number of holes h per eachaxial row can bereduced by abQut SQ I fromithatrequ'ired for circular, tuft holesjandstill p vide the same amount of fill for each irow. aresult a the brushof this invention is less expensive to make.

Also, advantages of using axiallyelongated tuft holes such as describedover full continuous slotsthat extend substantially'the axial lengthofia brush which are filled V with ,bristlesvarethat more individualbristlefaction is" obtained, less bristles are required, and overlappingtufts give an interrupted but completepatternofiaction to provide moreeffective polishing, sweeping or scrubbinglj" One manner of making theholesiin tubular blank is to use a machine having a carriage 30 mountedon the r frame 31 for reciprocal'movement (SeeFIGJB); The

carriage mounts members 3,2'that in turn mount a tubu lar blank 36'. Adrill 33 for drilling a circular holeis mounted by the frame to bereciprocallymoved perpendicular to the central axis of thetubeblank,-and is rotatably driven by suitable meanstnot shown). In

using this vmachine: with the tubular 'i-biank'imounted therein at oneendlof the reciprocallymovenient of carriage, the carriage istranslated; to move =the-.,tubulai' blank; axially; in onedirection'andtatstheisame time the drill is continuously moved downwardlyiuntil'the hole is drilled to its maximum depth and-thenthe drill iscon- 1tinuously moved upwardly until the" hole isqcompletedl,

The vertical reciprocal movementofthe-drillislcycled' r the number oftimes tocomplete the holes for arrow. 1

Even though the above refers to drillingholes, it is to be understoodthe holes, may be formed .by molding,

burning, casting or other methods, depending-onthe material that thetubular core is made from. Further, it

is to be understood that the'core needn-otj be tubular but maybe a solidcylinder.v v I Additionally, flat brushessu ch asside sweepfland scrubbrushes that have a generally cylindrical} tuft mountinghmember normallyrotated about-thescentral axis thereof and have tufts extendingoutwardlyof'the I generally flat surface thereof advantageously may havetuft holes provided in. the mounting member that are of 1 a shapepreviouslydescribed iie,v are of increasing dimensions frornadjacent thebottom offthe'holesfto the outer ends thereof With such side sweep" and,scrub brushes, it is preferred. that the direction of elongation of thetuft hol essare generally tral axis.

As examples of the invention, the tubular. brush of'example (a) thetubular core may have awallthiekness radially relative: said icen- TT'of0.437 inches, a hole that at the outer surface of" the tube is of anaxial dimension-X of 0,;437'inchand a transverse dimension D of 0.312,an axial hole spacing S between the center axes of adjacentholesiin thesame row of 0.75 inch and a tuft lengthlM that the outer end-s ofthe-tuft extends the core of 2.5 inches; while inthetubular brush ofexam s I ple tb) the dimensions correspondingrt setforth a above are0.53 inch; Q5 17 inchyQt36'8 tnch, L05 inch and 3425' inchrespeetively',and inthe tubular brush of V 7 example (0) thedimensionscorresponding tothose set forth above a are 0.562 inch; 0. 5.53 inch; 034 inch,1.20inch, and 4.25 inches respeetivelyl For each of the What isselaimedL A rotary brush that includes anaxially "elongatedv I tubular corehaving a central axis, a cylindricalouter surface'and a plurality ofspaced tuftedholes extending f a substantially radially relativethe?core-axis eachs'of said, l J 5 holes being, of progressively larger;areasin cross sec- 7 1 a :tions from theradial inward part of the holestoward" i the radialioutward part of the holesg each hole at theoutersurface of the core: being of a substantially greatermaximumdimensionl in one, direction'perpen V 'han ith'etmaxi s mi-rmdimensiontransverse --theretothat s perpendieu- :l artosaidradi'us V 1dieulari to a radius of; the outer surfa '2. The brush cream 1; further;ehara eri-zie'dj in that the, core is of a unitaryintegral!constructionV a,

3.1'lie -brushvoficlaiinl l 'furtherc haraeterizedinthat the firstmentioned dimension is .atilegtiabout to pen cent greater thanithetransversedimension; I I 4. The brush: oficlai'm 13 furtherchatacterized'in'that the first mentioned dimension: is parallel to thecentral axis.

5. The brushvof claim 44 further characterizedin that each hole has acentral axisgand. is of ashape that a plane of the hole central; axisthat is perpendicular to I the tube central axis. intersects the: tubewallpo'rtion def fining the hole at parallel lines:

6: A rotary brush that includes an outer surface and a pluralityof'spaeed'tuft'holes open; ing through said outerzsurface and extendinginwardly towardssaid axis, each; of: said holes being of asl'arge-rcross tsectionalareaat the outer surface than at a loea tion inwardlythereofleach hole at the the 7 core being of a substantially gr mensionin one direction perpendicu maximumdi the tufts tosaidicore,

t e s s" above examples; the included angleir'D'may be about 7 axiallyelongated 1 A brush core having a central ax'isaa generally cylindricalter surface off f I s to-a radius of s the outer surface than; themaximumdimension trans-1 7 verse'thereto that is perpendicui'ar to saidradius,la tuft. extendingineachiof said holes and means for securing a

